Hi mate
The hw is vehicle specific, but a basic summary is
Instrument cluster with cruise control
Steering column control unit (with indicator, window wipers and cc)
dynamic module
cover for under the steering column
then depending on spec,
plastic connector block and housing for dynamic module
wires and pin connecters for connector block
wiring diagram from BMW WDS
possible a FA coding (complete base coding) with added option 544
updating of all new HW with chassis number / info
coding
not that hard
But not what you would call a regular BMW retrofit